Army sources in Colombia say this will support an American-built intelligence centre, primed to supply the Colombians with information from satellites and spy planes, at Tres Esquinas in the south.

ECONOMIST: Colombia

But perhaps the biggest question facing Plan Colombia is what military response, if any, the three new battalions will meet when they head out from the Tres Esquinas base in their 60 helicopters.

ECONOMIST: Putumayo??s tense wait for the arrival of Plan Colombia

Based at Tres Esquinas, 145 kilometres (90 miles) from Puerto Asis, the prime task of these battalions, officials say, is to secure Putumayo, to enable police to attack its drug-processing laboratories and intensify their efforts to wipe out its coca plantations by spraying them with herbicides.

ECONOMIST: Putumayo??s tense wait for the arrival of Plan Colombia